Stardate 20011113.0928 (On Screen): At this point, it's looking like the most likely cause of yesterday's crash in NYC was an engine failure of some kind. If so, the most likely cause would be the engine throwing a turbine blade. This is more likely to happen on takeoff than at any other time, because that's when the engines are run at their maximum power levels. The housing of the engine cannot contain such debris, and what other damage it might do to the jet depends entirely on what direction it flies. And during takeoff the lost of an engine is worse than at any other time, because when a jet is near the ground there isn't sufficient time to recover from radical changes in the performance of the aircraft. One possibility is that the imbalance of torque made the jet perform an uncontrolled flat turn, which would put the rear stabilizer partially face-on to the air stream. That may well have been enough to snap it off, making it land in the bay separate from the main impact point. With the loss of the rudder, it would have been nearly impossible for the pilots to regain control of the jet.
But that's just me guessing. Investigators have had a day to look into it already and say there is no sign of foul play, especially from the cockpit voice recorder. I'm not the first to observe this, but it is a sign of the times that we heave a sigh of relief to learn that a jet crash that killed 255 people was "only" an accident. (discuss)
As to why the pilots didn't announce an emergency on the radio, the best guess is simply that they were too busy.
Update: Another possibility is that one or both of the engines ingested birds.
